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THE 






REFERENCE BOOK 



OF THE 



/ 



ENGINEERS' CLUB 



u3 



s 



OF 






PHILADELPHIA. 



Copyrighted and Published by the 

ENGINEERS' CLUB 

Of Philadelphia, Pa., U. S. A. 



TURNOUTS AND CROSSINGS. 

FORMUL>E FOR TURNOUTS AND CROSSINGS. 

John Marston, March 17th, 1883. 




Let 
g = gauge of track. 
d = distance between tracks. 
t ~ throw of switch-rail. 
n = number of the frog. 
n' = number of the middle frog in 

a three-throw switch. 
A = distance from heel of switch to 

toe of frog. 
A r = distance from heel of switch 

to toe of middle frog in a 

three-throw switch. 
x = distance between two frogs of 

a crossing. 
R — radius of turnout. 



= * (4^ 2 +l) 
9 



9* 



t n 2 q 
n = — 2- 



8^ 2 + l 



A* 

x = n (d — a) — / & 



These formulae are 
not absolutely accu- 
rate, but are near 
enough for practice. 
The only distance not marked on the diagram is x, which 
is the distance between the toes of the two frogs of a cross- 
ing, measured parallel to the main tracks. 

These formulae apply equally well on curves and straight 
lines, except that the radius of turnouts on curves is equal 

7? r v /?" 
to yv i nrf ^ the turnout be towards the convex side of 
JtC -j- K 



con- 



the track, and is equal to -^r^—™, ^ ^ be towards the 

cave side of the track. R! = radius of main track, i?" = 
radius of turnout on a straight line. 



Eng. Club, Phila. — Bef. Book. — Form 1. 






REDUCTION TABLES. 



REDUCTION TABLES 

TO FACILITATE MULTIPLICATION AND DIVISION. 

Howard Murphy, March 17th, 1883. 



Acres. 


Sq. Ft. 


Metres. 


l 


43560 


l 


2 


87120 


2 


3 


130680 


3 


4 


174240 


4 


5 


217800 


5 


6 


261360 


6 


7 


304920 


7 


8 


348480 


8 


9 


392040 


9 


10 


435600 


10 



Lin. Ft. 



3.280869 
6.561738 
9.842607 
13.123476 
16.404345 
19.685214 
22.966083 
26.246952 
29.527821 
32.808690 



Note. 

To prepare tables 
for other quantities, 
proceed by addition, 
thus: 



1 
2 
3 



1728 

1728 

3456 

1728 

5184 

1728 

etc. to 

17280 



10 

which latter, being 
ten times the origi- 
nal, checks the other 
additions. 



method 
From Less to Greater. 

Arrange, as usual, for di- 
vision. A glance at table 
divisor is 



set of fig- 



shows how often 
contained in first 
ures of dividend. Write 
this in quotient, and write, 
from table, its corresponding 
product under dividend. Sub- 
tract, proceed in same man- 
ner with remainder, etc. 

Example Sq.ft. to Acres. 
43560 ) 1655280 sq. ft. ( 38 ac. 
130680 
"348480 
348480 12728.4593724 ft. 

In examples, figures in italics are taken from tables. A 
table for any quantity may be made in two or three min- 
utes, and it pays to do so for even two or three operations. 



OF USE. 

From Greater to Less. 

Arrange, as usual, for 
multiplication with the 
greater unit as multiplier. 
Write separate products 
from table and add for final 
product. 
Example Metres to Feet 
3.280869 ft. 
3879.6 m. 
19685214 
29527821 
22966083 
26246952 
9842607 



ELECTRICAL FORMULA. 



ELECTRICAL FORMUL/E. 

Carl Herin«, June 2d, 1883. 

The units used in electrical calculations are as follows : 

Ampere — the unit of current strength — generally repre- 
sented by C. 

Volt — the unit of electro-motive force — generally repre- 
sented by E. 

Ohm — the unit of resistance — generally represented by 
E. 

Coulomb — the unit of quantity — generally represented 
by Q. Another unit of quantity is the "ampere-hour." 
Let it be represented by Q '. 

Farad — the unit of capacity — generally represented by 
0. As this is a very large unit the millionth part of it is 
generally used, and is called a micro-farad. 

Volt-coulomb — the unit of work — sometimes called a 
Vomb. Let it be represented by W. 

Volt-ampere or Ampere-volt — the unit of power — some- 
times called a Watt. Let it be represented by P. 

The following relations exist between these units : 

The strength of a current which has an electro-motive 
force of one volt and passes through a resistance of one 
ohm, is one ampere. 

A coulomb is the quantity of electricity which passes 
through a circuit in one second when the current strength 
is one ampere; therefore, an ampere is equal to a coulomb 
per second. The quantity which passes in one hour when 
the current strength is one ampere, is an ampere-hour, and 
is equal to 60x60 = 3600 coulombs. 

A farad is the capacity of a condenser which is charged 
to one volt with one coulomb. 

A volt-coulomb is the amount of work done when one 

Electrical Formula*— Pago A. 



6 ELECTRICAL FORMULAE. 

coulomb falls through a difference of potential or an elec- 
tro-motive force of one volt. 

A volt-ampere is the amount of power developed by a 
current of one ampere having an electro-motive force of 
one volt. As an ampere is a coulomb per second, a volt- 
ampere is a volt-coulomb per second. 

Using letters to represent the units, these relations may 
be expressed by the following formulae, in which t repre- 
sents one second and T one hour. 

C = E Q = Ct Q = CT = ^ 
W = QE P = CE 

As these relations contain no coefficient other than unity, 
the letters may represent any quantities given in terms of 
those units. For example, if E represents the number of 
volts electro-motive force, and R the number of ohms re- 

E 

sistance in a circuit, then their ratio ^ will give the num- 

ber of amperes current strength in that circuit. 

The above six formula? can be combined by substitution 
or elimination so as to give the relations between any of 
the quantities. The most important of these are the fol- 
lowing : 

Q= |t C = §t W^CEt = g 2 t = C 2 Rt=:Pt 

These are true, whether the letters represent the units or 
quantities measured in terms of these units. In the latter 
case the following are also true : 

Q, = 3600 Q' W = 3600 Q'E P = ^^M3 

besides all other combinations of these with those above. 



Electrical Formulae— Page B. 






ELECTRICAL FORMULAE. 



The values of these practical units in terms of the abso- 
lute or C. G. S. (centimeter-gram-second) units is as fol- 
lows: 



10- 1 

10 8 
10 9 

10- 1 
10- 9 

10 7 
10 7 



C. G. S. units. 



1 ampere 

1 volt 

1 ohm 

1 coulomb 

1 farad 

1 volt-coulomb 

1 volt-ampere 

The following tables give the numerical equivalents of 
the different units of mechanical and electrical energy. 

They give the actual equivalents, and, therefore, do not 
take into account the loss in converting one kind of energy 
into another, as that is dependent upon the particular ma- 
chine used. 

Equivalents of Work, 
work = power x time. 

(Heat, being only another form of work, is included in the general term, worlt.) 

Logarithm. 
0.0000000 
T. 8676580 
1.0083310 
4". 9800407 
4\ 7247682 
T- 3814342 
X 1272954 
2.349144] 
.3.1332698 
5.3551185 

0.0000000 

.1323420 
.9916690 
3.0199593 
3.2752318 
3.618565S 
2.8727046 
4.6508559 
2.8667302 
4.6448815 



] volt-coulomb = 



1 volt-ampere per sec. = 
1 foot-pound = 

1 kilogrammetre = 

1 pound-Fahr. unit of heat — 
1 pound-centigrade " = 

1 kilogr. -centigrade " = 
1 horse-power per second = 

44 per minute = 

1 force-de-cheval* per sec.= 

44 per min. = 



1.0000000 


volt-ampere per second 


.737324 


foot-pounds 


.101937 


kilogrammetres 


.00095508 


pound-Fahr. unit of heat 


.00053060 


pound-centigrade " 


.00024067 


kilogr. -centigrade " 


.00134059 


horse-power per second 


.000022343 


44 per minute 


.00135916 


force-de-cheval* per sec. 


.0000226526 


4; per min. 


1.0000000 


volt-coulomb 


1.35626 


volt-coulombs 


9.810000 


" 


1047.030 


'« 


1884.655 


" 


4154.950 


44 


745.941 


" 


44756.47 


" 


735.750 


" 


44145.00 


" 



* 1 force-de-cheval or French horse-power = 75 kilogrammetres per second. 



KlectricRl Formulae— Page C 



ELECTRICAL FORMULA. 



Equivalent of Power. 



work 





POWER = 


TIME 


















Logarithm. 






r i.ooooo 


volt-coulomb per second 


0.0000000 






.00134059 


horse-power 






3-.1272954 






.00135916 


force-de-cheval 


* 




3". 1332698 






.737324 


foot-pounds pei 


second 


1.867658') 






44.23944 


'* pei 


minute 


1.6458093 






2654.3664 


" pei 


hour 


3.4239606 






.101937 


kilogrammetres 


per 


sec. 


T-0083310 






6.11622 


" 


per 


min. 


.7864823 






366.9732 


" 


per 


hour 


2.5646336 






.00095508 


fpound-Fahr. ) 
[ units of heat \ 


per 


sec. 


4:. 9800407 


1 volt-ampere = 


H 


.0573048 


" 


per 


min. 


"2-7581920 






3.438288 


pound- } 


per 


hour 


.5363433 






. 00053060 < 


centigrade > 
^units of heat ) 


per 


sec. 


4". 7247682 






.0318360 


" 


per 


min. 


2". 5029195 






1.910160 


f kilogram- ^ 


per 


hour 


.2810708 






.000240670 < 


centigrade V 
[ units of heat) 


per 


sec. 


4- 3814342 






.0144402 


" 


per 


min. 


2M595855 






.866412 


" 


per 


hour 


T-9377368 


1 volt-coulomb per sec. 


= 


1.000000 


volt-ampere 






0.0000000 


1 horse-power 


= 


745.941 


volt-amperes 






2.8727046 


1 force-de-cheval* 


ss 


735.750 


" 






2.8667302 


1 foot-pound per sec. 


== 


1.35626 


" 






.1323420 


" per min. 


= 


.0226043 


" 






2". 3541907 


" per hour 


= 


.0003767380 


" 






4". 5760394 


1 kilogramme tre per sec. 


== 


9.8100000 


ii 






.9916690 


" per min 


= 


.163500 


" 






T-2135177 


11 per hour 




.00272500 


" 






"3.4353664 


1 pound- "} 














Fahrenheit v per sec. 


= 


1047.030 


" 






3.0199593 


unit of heat j 














" per min. 


= 


17.4505 


" 






1.2418080 


" per hour 




.290842 


M 






T-4636567 


1 pound- I 














centigrade V per sec. 


= 


1884.655 


" 






3.2752318 


unit of heat j 














" per min. 


= 


31.41091 


CI 






1.4970805 


11 per hour 


== 


.523515 


«{ 






Y- 71 89202 


1 kilogram- ^ 














centigrade V per sec. 


== 


4154.950 


• ( 






3.6185658 


unit of heat J 














11 per min. 


= 


69.2492 


" 






1.8404145 


" per hour 


= 


1.154153 


" 






.0622632 



The following examples will illustrate the use of the 
foregoing tables : 

I. How many incandescent lamps, requiring an electro- 
motive force of 60 volts and a current of 1.5 amperes each, 
can be supplied by an engine giving 15 useful H. P.? 



Electrical Formulae — Page D. 



ELECTRICAL FORMULA. 



9 



If the loss of energy in the dynamo is 20 per cent., 
then 80 per cent, of 15, = 12 will be the H. P. of current 
available. From the tables, 1 H. P. = 746 volt-amperes; 
1 lamp requires 1.5x60 = 90 volt-amperes; therefore, 

— cS_ — = 100 lamps very nearly. 

II. What H. P. is required to supply 100 lamps of 40 
ohms resistance each, requiring an electro-motive force of 
60 volts? 

The number of volt-amperes for each lamp is =j- ~ 

From the tables, 1 volt-ampere = .00134 H. P.; there- 
to 2 
fore, -^- X 100 X .00134 = 12 H. P. (electrical) very nearly. 

If the loss in the dynamo is 20 per cent., then 12 H. P. 
is 80 per cent, of the actual H. P. required; therefore, 
12 



.80 



= 15 H. P. 



Electrical Formulae — Page E. 



10 CONVENTIONAL COLORE 



CONVENTIONAL COLORS, 

Prof. L. M. Haupt, Oct. 20th, 1883, 



_ . , J Exterior Lt. red with, carmine 1 c 

Brick < n , , > 

( Section Crimson lake or carmine J 



Brass J Exterior Gamboge. 

[. Interior Dark Indian yellow. 

or Dragon's 

blood. 

Brushwood Green and burnt sienna, marbled. 

Buildings Crimson lake. 

Buildings, shadows of Indigo, burnt sienna and lake. 

Cast iron Payne's gray. 

Clay or earth Burnt umber. 

Concrete work Sepia. 

Contours India ink, sepia, or burnt sienna. 

Copper Gamboge and crimson lake. 

Cultivated land Burnt sienna. 

Earth and clay . . . . , Burnt umber. 

Fir timber Indian yellow. 

Granite • . Violet carmine. 

Grass Light Hooker's green (No. 1). 

travel Yellow ochre dotted with burnt sienna. 

Gun metal , Dark cadmium or orange. 

T ( Cast Payne's gray. 

Iron < j m i 

(Wrought Prussian blue and indigo. 

( Preliminary Bine. 

Lines -j Changes in Eed. 

( Location, final Black, 

Mahogany Indian red. 

Meadow land Hooker's green (Ho. 1). 

Mud Sepia or India ink. 

0«k timber Burnt sienna, grained. 

Roads and streets Yellow ochre and sepia. 

Sand Yellow ochre. 

Sky Cobalt. 

Slopes Sepia with burnt umber. 

Steel Indigo or Prussian blue and lake. 

Stone . . Sepia and yellow ochre. 

("Light Gamboge and burnt sienna"| on a 

Trees < Shade Gamboge and indigo >■ green 

(^Shadows Burnt sienna and indigo J ground. 

Uncultivated land Green and burnt sienna, marbled. 

Vineyards • Purple. 

Water Indigo or Prussian blue. 

w a / Exterior Yellow ochre or raw sienna. 

\ Sections * Burnt sienna. 

Wrought iron .... . Prussian blue and indigo. 



ROADS, STREETS AND PAVEMENTS. 11 



ROADS, STREETS, AND PAVEMENTS. 

Chas. H. Haswell, Nov. 3d, 1883. 

CLASSIFICATION OF ROADS. 

1. Earth. 2. Corduroy. 3. Plank. 4. Gravel. 5. 
Broken stone (Macadam). 6. Stone sub-pavement with 
surface of broken stone (Telford). 7. Stone sub-pavement 
with surface of broken stone and gravel, or gravel alone. 
8. Rubble stone bottom with surface of broken stone or 
gravel, or both. 9. Concrete bottom with surface of 
broken stone or gravel, or both. 

GRADE OF ROADS. 

Limit of practicable grade varies with character of road 
and friction of vehicle. For best carriages on best roads, 
limit is 1 in 35, or 151 feet in a mile. 

Maximum grade of a turnpike road is 1 in 30 feet. An 
ascent is easier for draught if taken in alternate ascents 
and levels, than in one continuous rise, although the ascents 
may be steeper than in a uniform grade. 

Ordinary angle of repose is 1 in 40 if roads are bad, and 
1 in 30, to 1 in 20. 

When roads have a greater grade than 1 in 35, time is 
lost in descending, in order to avoid unsafe speed. Grade 
of a road should be less than its angle of repose. Minimum 
grade of a road to secure effective drainage should be 1 in 
80. In France it is 1 in 125. 

In construction of roads the advantage of a level road 
over that of an inclined one, in reduction of labor, is 
superior to cost of an increased length of road in the avoid- 
ing of a hill. 

Alpine roads over the Simplon Pass average 1 in 17 on 

Koads, Streets and Pavements — Page A. 



12 



ROADS, STREETS AND PAVEMENTS. 



Swiss side, 1 in 22 on Italian side, and in one instance 1 in 
13. 

In deciding upon a grade, the motive power available of 
ascent and avoidable of waste of power in descending are to 
be first considered. 

When traffic is heavier in one direction than the other, 
the grade in ascent of lighter traffic may be greatest. 

When axis of a road is upon side of a hill, and road is 
made in parts by excavation and by embankment, the side 
surface should be cut into steps, in order to afford a secure 
footing to embankment, and in extreme cases, sustaining 
walls should be erected. 

CONSTRUCTION. 
ESTIMATE OF LABOR IN CONSTRUCTION OF ROADS. 

(if. Ancelin.) 

A day's work of 10 hours of an average laborer is esti- 
mated as follows : 

fn Cube Yards. 



Work. 


Ordinarv 
Earth. 


Loose 
Earth. 


Mnd. 


Clay and 
Earth. 


Gravel. 


Blasting 
Eock. 


Picking and digging . . . 
Excavation and pitching ) 

6 to 12 feet j 

Loading in barrows . . . 
Wheeling in barrows ) 

per 100 feet \ 

Loading in carts .... 
Spreading and levelling . 


18 to 23 

8 to 12 

22 

20 to 33 

16 to 48 
44 to 88 


16 

8 


7 to 16 
8 

25 


9 
4 


7 to 11 

19 

24 to 28 

17 to 27 
30 to 80 


2.4 

2.2 



Time of pitching from a shovel is one-third of that of 
digging. 

Ditches. — All ditches should lead to a natural water- 
course, and their minimum inclination should be 1 in 125. 

Depressions and elevations in surface of a roadway in- 
volve a material loss of power. Thus, if elevation is 1 
inch, under a wheel 4 feet in diameter, an inclined plane of 



Roads, Streets aud Pavements— Page B. 



ROADS, STREETS AND PAVEMENTS. 13 

1 in 7 has to be surmounted, and, as a consequence, one- 
seventh of weight has to be raised 1 inch. 

An unyielding foundation and surface are indispensable 
for a perfect roadway. 

Earth in embankment occupies an average of one-tenth 
less space than in natural bank, and rock about one-third 
more. 

Ruts. — Surface of a roadway should be maintained as 
intact as practicable, as the rutting of it not only tends to 
a rapid destruction of it, but involves increased traction. 

The general practice of rutting a road displays a degree 
of ignorance of physical laws and mechanical effects that is 
as inexplicable as it is injurious and expensive. 

On compressible roadways, as earth, sand, etc., resistance 
of a wheel decreases as breadth of tire increases. 

Depressing of axles at their ends increases friction. 
Long and pliant springs decrease effect of shock in passing 
over obstacles in a very great degree. 

Transverse Section. — Best profile of section of roadway is 
held to be one formed by two inclined planes meeting in 
centre of road and slightly rounded off at point of junction. 

Roads having a rough surface or of broken stone should 
have a rise of 1 in 24, equal to a rise on crown of 6 ins., 
and on a smooth surface, as a block-stone or wood pave- 
ment, the rise may be reduced to 1 in 48. 

On roads, when longitudinal inclination is great, the rise 
of transverse section should be increased, in order that sur- 
face water may more readily run off to sides of roadway, 
instead of down its length, and consequently gullying it. 

Stone Breaking. — A steam stone-breaking machine will 
break a cube yard of stone into cubes of 1.5 ins. side, at 
rate of 1 to 1.5 H.P. per hour. 



Roads, Streets and Pavements — Page C. 



ROADS, STREETS AND PAVEMENTS. 
MACADAMIZED ROADS. 

In construction of a Macadamized road, the stones (road 
metal) used should be hard and rough, and cubical in 
form, the longest diameter of which should not exceed 2.5 
ins., but when they are very hard this may be reduced to 
1.25 and 1.5 ins. 

The best stones are such as are difficult of fracture, as 
basaltic and trap, and especially when they are combined 
with hornblende. Flint and siliceous stone are rendered 
unfit for use by being too brittle. Light granites are ob- 
jectionable, in consequence of their being brittle and liable 
to disintegration ; dark granites, possessing hornblende, are 
less objectionable. Limestones, sandstones, and slate are 
too weak and friable. 

Dimensions of a hammer for breaking the stone should 
be, head 6 ins. in length, weighing 1 lb., handle 18 ins. in 
length ; and an average laborer can break from 1.5 to 2 
cube yards per day. 

Stones broken up in this manner have a volume twice as 
great as in their original form. 100 cube feet of rock will 
make 190 of 1.5 ins. dimension, 182 of 2 ins., and 170 of 
2.5 ins. A ton of hard metal has a volume of 1.185 cube 
yards. 

Construction of a Roadway, — Excavate and level to a 
depth of 1 foot, then lay a "bottom" 12 ins. deep of brick 
or stone spalls or chips, clinker or old concrete, etc., roll 
down to 9 ins., then add a layer of coarse gravel or small 
ballast 5 ins. deep, roll down to 3 ins., and then metal in 
two equal layers of 3 ins., laid at an interval, enabling first 
layer to be fully consolidated before second is laid on and 
rolled to a depth of 4 ins. ; a surface or " blind " of .75 
inch of sharp sand should be laid over last layer of metal 
and rolled in with a free supply of water. 

Roads, Streets and Pavements— Page D. 



ROADS, STREETS AND PAVEMENTS. 



15 



Proportion of Getters, Fillers, and Wheelers in different Soils. 
Wheelers computed at a Run of 50 Yards. (Molesworth.) 





Get- 
ters. 


Fill- 
ers. 


Wheel- 
ers. 




Get- 
ters. 


Fill- 
ers. 


Wheel- 
ers. 


Loose earth, ) 

sand, etc. j * * 
Compact earth . . 
Marl 


1 

1 
1 


1 

2 
2 


1 

2 
2 


Hard Clay . . . 
Compact ) 

gravel $ * 
Rock 


1 

1 
3 


1.25 
2 

1 


1.25 

1 
1 



TELFORD ROADS. 

In construction of a Telford road, metalling is set upon 
a bottom course of stones, set by hand, in the manner of 
an ordinary block stone pavement, which course is com- 
posed of stones running progressively from 3 inches in 
depth at sides of road to 4, 5, and 7 inches to centre, and 
set upon their broadest edge, free from irregularities in 
their upper surface, and their interstices filled with stone 
spalls or chips, firmly weighed in. 

Centre portion of road to be metalled first to a depth of 
4 ins., to which, after being used for a brief period, 2 ins. 
more are to be added, and entire surface to be covered, 
"blinded/' with clean gravel 1.5 ins. in depth. 

Telford assigned a load not to exceed 1 ton upon each 
wheel of a vehicle, with a tire 4 ins. in breadth. 

GRAVEL OR EARTH ROADS. 

In construction of a gravel or earth road, selection should 
be made between clean round gravel that will not pack, 
and sharp gravel intermixed with earth or clay, that will 
bind or compact when submitted to the pressure of traffic 
or a roll. 

Surface of an ordinary gravel roadway should be exca- 
vated to a depth of from 8 to 12 ins., for full width of 
road, the surface of excavation conforming to that of road 
to be constructed. 

Ui/add, Streets aud Paveineuta — Pa^e E 



16 . ROADS, STREETS AND PAVEMENTS. 

The gravel should then be spread in layers, and each 
layer compacted by the gradual pressure due to travel over 
it, or by a roller, the height of it increasing with each 
layer. One of 6 tons will suffice for limit of weight. 

If gravel is dry and will not readily pack, it should be 
wet, and mixed with a binding material, or covered with a 
thin layer of it, as clay or loam. 

In rolling, the sides of road should be first rolled, in 
order to arrest the gravel, when the centre is being rolled, 
from spreading at the side. 

To re-form a mile of gravel or earth road, 30 feet in 
w T idth between gutters, material cast up from sides, there 
will be required 1640 hours' labor of men, and 20 of a 
double team. 

CORDUROY ROADS. 

A corduroy road is one in which timber logs are laid 
transversely to its plane. 

PLANK ROADS. 

A single plank road should not exceed 8 feet in width, 
as any greater width involves an expenditure of material 
without any equivalent advantage. 

If a double track is required it should consist of two 
single and independent tracks, as with one wide track the 
wear would be mostly in the centre, and consequently, 
w T ear would be restricted to one portion of its surface. 

Materials. — Sleepers should be as long as practicable of 
attainment, in depth 3 or 4 ins., according to requirements 
of the soil, and they should have a width of 3 ins. for each 
foot of width of road. 

Pine, oak, maple, or beech are best adapted for economy 
and wear. 

Planks should be from 3 to 3.5 ins. thick, and not less 

Roads, Streets and Pavements — Page P. 






f / 



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